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Yep, broke 10,000 on my MP250A

It's been a lot more reliable than I thought it would have. That's the good news.

Now, for the bad. In the last two weeks I have been a victim of TFOB (things falling off bike).

The first was I lost one of the two muffler bolts. Bummer, but at least I had the other to take to the parts store and get a M10x1.25x50. The correct length would have been a 55mm, but nobody had a 55, only 50 or 60. I got the 50mm and it works good, put threadlocker on it this time.

Now the scary bad news. I noticed a slight shimmy in my rear wheel. I was only a couple miles away so figured I would check it once I got home. Bad mistake, as now I have no axle nut. Yep, it's gone. Turns out the 'ROKETA MC-54B AUTO-LOCKING NUT M14' isn't so auto locking after all.

So now I am looking locally for the nut. Does anyone have the exact size for the axle nut? M14 is one clue, but what thread pitch?

Thanks.

I agree. I know from experience when my bike was stalling that the clutch will remain engaged until very low speeds.

The only way to keep the engine from turning is to remove the belt.

Nah, it won't harm anything. The pressure is already there, and trust me, looks for any hole to oil out of.

Sounds as if the clutch boss is sticking. The clutch gets dirt and grime in between the boss and slider disk, causing it to seize and stick. It happened to mine. I had to disassemble the clutch using a 1 and 13/16 inch socket attached to an impact wrench, then cleaned and applied whith lithium grease to the boss and slider disk. There are some videos on Youtube of how to disassemble the clutch.

Not absolutely sure on rollers, but mine came with an 856x23 Gates Powerlink belt.

The problem though is that the symptoms are sometimes not that black and white. Take my bike, for example. It never would make the classic rich or lean sounds, no popping, no backfiring. What i noticed, only over time, was a pattern in how it would act. It runs better in the morning than the afternoon. In the morning I could go full throttle, the afternoon it would cut out after 3/4 throttle. I ride 45 miles home, and it would cut out almost in the exact same locations every day. The only commonality was temperature, humidity, and load. In the morning, the cooler, less dense air would mask the richness. The warm, more dense (especially with humidity in Florida) air would bring out the rich symptoms. The hills I ride through would really load the bike, and it would stall. 30 seconds of cranking would get me to the next hill. But then once I passed through the hills, the last 15 miles would be stall free. The symptoms never added up to rich OR lean. Until.....

I kept asking myself why a bike with the same jets and mixture as last year would suddenly not run right this year. Nothing had changed, other than the age of the rubber materials in the carb. Why should I be changing jets when it ran fine before? Seems I would be masking some other problem. The valves, vacuum, and all the other suspects were ruled out over time.

After playing with the float for almost two straight weeks, here's what I noticed. The float shutoff valve would either be fully closed allowing in no gas at all, or the carb would flood from too much fuel. There was no happy medium. I adjusted the float tang all through its range, and it still would either not open or flood. I only noticed the flooding once I installed a clear bowl drain hose, so I could monitor the fuel level real-time.

So, in my opinion based on weeks of toying with this, is that the rubber stop on the float valve gets worn (it still LOOKS the same to me). It's just not doing the job anymore of controlling the flow. After all, my scoot is 7 years old, and who knows how much older the carb is.

I also have a new carb on the way. Hopefully, this does it. But, like rsw1158, a new carb (or even a rebuild kit) may be the solution to a whole lot of these Jonways having the same stalling issue.